Succinic diethyl ester

Moreover, succinic diethyl ester was former 1 from the malotnc acid, and adipic diethyl ester from the suermie acid. 

The DuPont company used the succinic acid ester process, in which diethyl succinate is first cyclised to diethyl succinylsuccinate (2.39) in a sodium/alcohol mixture. One mole of the product is next condensed with two moles of aniline under oxidising conditions, forming diethyl 2,5-dianilino-3,6-dihydroterephthalate (2.40). Ring closure at 250 °C gives dihydroquinacridone, from which quinacridone is obtained by oxidising away the two extra hydrogen atoms. 

According to Thurston (702), the lower dibasic esters yield pure carbox5unonoguanamines so readily that this reaction is an excellent synthetic route, when confined to the lower esters. It has been apphed to 1-aryl- and alkyl-biguanides as usual, and to the alkali metal salts of half esters. The reaction involving diethyl malonate is represented below succinic acid esters (292, 699) react similarly. 

ETHYL ENANTHYLSUCCINATE (Succinic acid, heptanoyl-, diethyl ester)... 

Diethyl propionylsuccinate Succinic Acid, propionyl-, diethyl ester (8) Butanedioic Acid, 1-oxopropyl-, diethyl ester (9) (41117-76-4)... 

OB to C02 —65.37% v hygr prisms (from acetic acid + benz) mp 87.5°. V sol in acetic acid si sol in benz insol in petr eth. Prepn is by heating bromomethylmalonic acid diethyl ester with Na azide dissolved in aq ethanol. Its Ag salt, Silver Azido-iso-Succinic Acid, color cryst, deton violently on heating (Refs 1, [272]... 

CH2,CH2,C02Et. From the latter the three-carbon unit of diethyl succinate may be recognised, and the Stobbe condensation is a suitable illustration of this process. Thus the reaction of aldehydes or ketones with succinic esters in the presence of potassium t-butoxide (or with sodium hydride) gives alkylidene-succinic acid esters (25). The reaction is somewhat slower in the case of the less basic sodium ethoxide. 

N1 - SUCCINIC ACID. MERCAPTO-, DIETHYL ESTER, S-a tar with , 0-OIMETHYL PHOSPHOROOITHIOATE... 

SUCCINIC ACID, HERCAPTO-, DIETHYL ESTER, S-ester with 0,0-DIMETHYL PHOSPHORODITHIOATB... 

Thus the diethyl ester of succinic acid is formed from ethyl potassium malonate ... 

The Brown-Walker 1 method has been found to be of excellent service in the electrolysis of the potassium salts of the mono-esters of malonie acid. The formation of the diethyl ester of succinic acid from ethyl potassium malonate has already been mentioned fp. 103). 

SYNS BUTANEDIOIC ACID, DIETHYL ESTER DIETHYL SUCCINATE (FCQ ETHYL SUCCINATE FEMA No. 2377... 

An efficient enzyme-catalyzed reaction for the large-scale preparation of (R)-2-iso-butyl succinic acid 4-ethyl ester (R)-2a, a key intermediate in the synthesis of collagenase inhibitor R00319790 (1), is described (Fig. 1). The corresponding racemic diethyl ester substrate 9 is applied at 20% concentration and hydrolyzed re-gio- and enantioselectively ( >100) at the sterically more hindered secondary ester group using a cheap commercial subtilisin preparation. The desired (R)-monoacid is separated from the remaining antipodal diester (S)-9 by means of extraction and obtained in > 99% ee and > 43% yield. The development of the reaction from process research to the pilot-scale is described. 

By retro synthetic analysis collagenase inhibitor RO0319790 (1) can be assembled from two chiral building blocks, (R) -succinate 2 and (S)-tert-leucine N-methyla-mide 13. As the latter can be prepared from commercially available (S)-tert-leucine 8 our work concentrated in particular on the construction of the first building block 2. In order to assemble the carbon skeleton of 2 in the most efficient way, extremely cheap maleic anhydride 4 was converted in a known ene reaction with isobutylene to provide the cyclic anhydride 6. Hydrogenation of the double bond followed by the addition of EtOH/p-TsOH yielded the racemic diethyl ester substrate 9 for the enzyme reaction. The enzymatic monohydrolysis of 9 afforded the monoacid (R)-2a. (R)-2 a was coupled via its acid chloride with leucine amide 13 to ester 14, which finally was converted into the hydroxamic acid 1. 

Sommelet reaction, 33, 93 Sorbic acid, 5-hydroxy-/3-methyl, J-lactone, 32, 57 Stannic chloride, 33, 91 Stearic acid, 34, 15 Stearone, 33, 84 cis-Stilbene, 33, 88 fraws-Stilbene, 33, 89 Stirrer, for caustic fusion, 30, 104, 105 seal for, 30, 54 Stobbe condensation, 30, 18 Styrene, 33, 72 34, 85 reaction with sulfuric acid, 35, 83 Styrene dibromide, 30, 73 Styrene oxide, 31, 3 0-Styrenesulfonyl chloride, 34, 85 Succinic acid, 34, 44 Succinic acid, < -benzhydrylidene-, a-ETHYL ESTER, 30, 18 CLNNAMYL-, 31, 85 DIPHENYL ESTER, 34, 44 HEPTANOYL-, DIETHYL ESTER, 34, 51 PHENYL-, 30, 83 Succinic anhydride, 34, 40 SUCCINONITRILE, a, -DIPHENYL-, 32, 63 Sulfide, methyl 2-thienyl, 35, 85 Sulfonation of styrene, 34, 85 Sulfonyl chloride, from sodium sulfonate, 34, 85... 

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